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प्रश्न
Ice kept in a beaker, slowly melts and turns into water. The water in the beaker on solidification is freezing turns back to ice. Give four reasons why the change from ice to water and water back to ice is considered a physical change.
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उत्तर
Both changes are physical changes since
- The change is – temporary
- It is a reversible change
(heating and cooling reverse the change)
heating of ice – turns it into the water,
cooling of water – turns it back into ice - No new products are formed since both ice and water are chemical – ‘H20’
- Properties of the original substance are not altered.
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संबंधित प्रश्न
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| Column A | Column B |
| 1. a change which cannot be easily reversed | a. man-made change |
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| 5. a change where no new substance is formed | e. irreversible change |
| f . slow change |
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